Electric heating unit



Nov. 11, 1924- 1,515,231

E. E. SUTHERLAND ELECTRIC HEATING UNIT Filed Jan. 25, 1924 Fig.3. a4 a1 15 as as as 22 16 4 Fig.5.

23 a 2 "1 r "ii O' GQGGOOIOO 5 Fig.6. 2

2s m g; W55? WITNESSES: I ,INVENTOR M ErnesfESufher/and.

Patented Nov. 11, 1924.

UNITED STATES PATENT OFFICE.

OHIO, ASSIGNOR T WESTINGHOUSE ELEC- A CORPORATION OF PENNSYLVANIA.

ELECTRIC HEATING UNIT.

Application filed January 25, 1924. Serial No. 688,380.

To all whom it may concern Be it known that I, EnNnsr E. SUTHER- LAND, a citizen of the United States, and a resident of Mansfield, in the county of Richland and State of Ohio, have invented a new and useful Improvement in Electric Heating Units, of which the following is a specification.

My invention relates toelectric heating devices and particularly to electric heating units.

The object of my invention is to provide a relatively simple, compact and light-weight open electric heating unit.

In practicing my invention, I provide an upper and a'lower skeleton frame of cast metal and a plurality of bars, of refractory electric-insulating material, located therebetween and having interfitting tongue and groove portion respectively. A plurality of resistor members extend through openings in the bars and are each symmetrically distributed over the unit.

In the single sheet of drawings,

Figure 1 is a top plan view with portions cut away and a portion shown in section, of

a heating unit embodying my invention,

' Fig. 2 is a view in end elevation thereof,

ig. 3 is a view, in vertical section therethrough, taken on the line IIIIII of Fig. 1,

Fig. 4 is a view, in front elevation, of a refractory bar constituting a part of the heating unit,

Fig. 5 is a view, in end elevation, of the refractory bar illustrated in Fig. 4, and Fig. 6 is a fragmentary view, in lon itudinal section, taken on the line VI I of Fig. 4, of the refractory bar.

A heating unit 11 comprises a lower skeleton frame 12 and an upper complementary skeleton frame. 13, each of cast metal, preferably of cast iron. Both frames comprise a relatively narrow peripheral portion 14,

v and a plurality of laterally extending rib members 15 and 16, respectively. In addition, the bottom frame comprises a plurality of feet 17 located at the corners of the substantially rectangular peripheral portion 14.

A plurality of handles 18 are cast integral with the bottom portion 12 and a terminal-supporting and cover member 19 is also cast integral with the bottom frame, at substantially the middle portion of the side opposite to that at which the handle members 18 are located.

The rib members 15 and 16 in the respec tive frames, are spaced apart a suitable distance and are provided on the inner surfaces thereof with integral, longitudinallyextending tongue portions 21 and 22, respectively.

Elongated and relatively narrow refractory members 23, of a suitable refractory electric-insulating material are located between the co-operating upper and lower rib members 15 and 16.

The top and bottom surface of the members 23 are provided with grooves 24 and 25, within which the respective tongue portions 21 and 22 may fit in order to hold the refractory resistor-supporting member 23 in its proper operative position between the upper rib member 15 and the lower rib member 16, which are located in oppositely spaced relation relatively to each other, substantially as illustrated in Fig. 3 of the I drawings.

Each of the refractory bars 23 is provided with a plurality of symmetrically spaced openings 26 extending laterally therethrough and is further provided with a plurality of longitudinally-extending grooves 27 in one surface thereof for a purpose to be hereinafter set forth. grooves 27 co-operating with two of the laterally extending openmgs 26, is more particularly illustrated in Fig. 6 of the drawing.

A pair of resistor members 28 and 29, each comprising a helically wound resistor wire of a suitable material, such as nichrome, extend through the respective openings 26 in the spaced bars 23,and also extend therebetween. ,Each resistor member extends through the openings 26 and between the bars 23, in such manner that both resistor members are distributed substantiall uniforml over the surface area of the eating unit. Three terminal pins 31, 32 and 33 are insulatedly mounted in the member 1 9 and have the respective ends of the resistor members 28 and 29 electrically connected thereto, in such manner that the One of the i j acent openings 26 lton frames.

sistor member 28 extends through openings '28 located adjacent to those openings 26 through which the reand on the outside of sister member 29 extends.

a By reason of the fa'ct thatthe walls of the outer openings 26 extendlthe full thickness of the member 23, the resistor'ineinber'28 will lie in a position outside of and spaced from the resistor member 29, and this position will be maintained even though the "two resistors are gepera'ad at' a relativel high temperature and ma sag slightly;

Means for holding'the two skeleton frames 12 and 13 in their proper superposed positions on each side of the respective members 23 may comprise a plurz ility of machine screws 34, one of each of which is "hea ed at the corner of the skele- Each of the machine screws 34 is provided with a cooperating nut 35 and.

a washer 36 of theusual construction.

The deviceembodying my invention provides a relatively open heating unit in which the major portion of-the resistor member is uncovered and heatmay be transmitted by radiation only, and itfurther provides a relatively small amount of supporting ma- 1 'terial necessary to be heated bythe resistor ,member whereby its initial speed or rate of therprovidesa mg unit comprising 7 elements, each of which are substantially heating up; is greatly increased.

' The deviceembodying my invention furrelatively light-weight heata plurality of heating symmetrically or uniformly distributed over the surface area of theheating unit.

Various modifications and changes may be madewithout departing from the spirit and scope of the invention, and I desire therefore that only suchlimitations shall be imposed thereon as are set forth in the appended claims. a

'I claim as my invention:

, 1, -A light weight electric heating unit ;c(uT-1prising substantially coextensive upper and lower skeleton frames, a plurality of.

, spaced and parallel-extending bars, of refractory electric-insulating material, located betweensaidframes, each having a plurality of openings extending ,laterally there through, and a resistor member extending member operative and through and interiitting therewith, means i' clamping said frames together, and a resistor member extending through the openings in said bars and distributed substantially uniformly over the surface area of the heatlng unit. I A

8. A light weight electric heating unit comprising substantially coextensive upper and lower skeleton frames, a plurality of spacedand parallel-extending bars, of refractory electric-insulating material located between said frames, v of openings extending through, said frames and bars having'interfitting tongue and'groove portions, means forsecuring said frames against said bars, and a resistor member extending throughthe openings in said bars and distributed substantially uniformly over the surfacearea of the-heating unit. j

4. A light weight electric heating unit comprising substantially coextensive upper and lower skeleton frames, a plurality of spaced and parallel-extending bars, of refractory electric-insulating material, located between said frames, each having a plurality of -.openings extending laterally therethrough, said frames and bars having inter' fitting tongue and groove portions, means for securing said frames 'againstsaidbars, a resistor member extending through the openings in said'bars and distributed substantially uniformly over the surface area of the heating unit, and terminal members for said resistor insulatedly mounted on one of said frames. i

5. In an electric heating unit, in" combination, a lower skeleton frame, of metal, comprising a peripheral'portion, of substantially rectangular contour, and aplurality of spaced and parallel-extending integral ribs, an upper clamping frame substantially complemental to said lower frame, a plurality of bars, of refractory electric-insulating material each having a plurality of spaced openings extending'laterally therethro-ugh, said bars having grooved surfaces interfitting wlth tongue portions on said each having a pluralityvv laterally 'there- In an electric heating unit in combination, a lower skeleton frame, of metal, comprising a peripheral portion, of substantially rectangular contour, and a plurality of spaced and parallel-extending integral ribs, an upper clamping frame substantially complemental to said lower frame, a plurality of bars, of refractory electricinsula-ting material each having a plurality of spaced openings extending laterally there through, said bars having grooved surfaces interfitting' with tongue portions on said ribs, means for clamping said upper and lower frames against said refractory bars, a plurality of resistor members extending through the openings in said bars and each distributed substantially uniformly and symmetrically over the surface area of said heating unit, and a plurality of terminal members insulatedly mounted on said lower frame.

7. An electric heating unit comprising substantially coextensive upper and lower skeleton frames, a plurality of spaced bars, a refractory electric-insulating material located between said frames, each having a plurality of openings extending laterally therethrough, and a resistor member extending through the openings in said bars and distributed over the surface area of the heating unit.

In testimony whereof I have hereunto subscribed my name this sixteenth day of January 1924.

ERNEST E. SUTHERLAND. 

